/*******************************************************************************
 * Copyright 2011, 2012 Chris Banes.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.ruint.lib.pulltorefresh.library;

import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.os.Build.VERSION;
import android.os.Build.VERSION_CODES;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.ListAdapter;
import android.widget.ListView;

import com.ruint.corelib.R;
import com.ruint.lib.pulltorefresh.library.internal.EmptyViewMethodAccessor;
import com.ruint.lib.pulltorefresh.library.internal.LoadingLayout;

public class PullToRefreshListView extends PullToRefreshAdapterViewBase<ListView> {

  private LoadingLayout mHeaderLoadingView;
  private LoadingLayout mFooterLoadingView;

  private FrameLayout mLvFooterLoadingFrame;

  private boolean mListViewExtrasEnabled;

  public PullToRefreshListView(Context context) {
    super(context);
  }

  public PullToRefreshListView(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  public PullToRefreshListView(Context context, Mode mode) {
    super(context, mode);
  }

  public PullToRefreshListView(Context context, Mode mode, AnimationStyle style) {
    super(context, mode, style);
  }

  @Override
  public final Orientation getPullToRefreshScrollDirection() {
    return Orientation.VERTICAL;
  }

  @Override
  protected void onRefreshing(final boolean doScroll) {
    /**
     * If we're not showing the Refreshing view, or the list is empty, the the
     * header/footer views won't show so we use the normal method.
     */
    ListAdapter adapter = mRefreshableView.getAdapter();
    if (!mListViewExtrasEnabled || !getShowViewWhileRefreshing() || null == adapter || adapter.isEmpty()) {
      super.onRefreshing(doScroll);
      return;
    }

    super.onRefreshing(false);

    final LoadingLayout origLoadingView, listViewLoadingView, oppositeListViewLoadingView;
    final int selection, scrollToY;

    switch (getCurrentMode()) {
      case MANUAL_REFRESH_ONLY:
      case PULL_FROM_END:
        origLoadingView = getFooterLayout();
        listViewLoadingView = mFooterLoadingView;
        oppositeListViewLoadingView = mHeaderLoadingView;
        selection = mRefreshableView.getCount() - 1;
        scrollToY = getScrollY() - getFooterSize();
        break;
      case PULL_FROM_START:
      default:
        origLoadingView = getHeaderLayout();
        listViewLoadingView = mHeaderLoadingView;
        oppositeListViewLoadingView = mFooterLoadingView;
        selection = 0;
        scrollToY = getScrollY() + getHeaderSize();
        break;
    }

    // Hide our original Loading View
    origLoadingView.reset();
    origLoadingView.hideAllViews();

    // Make sure the opposite end is hidden too
    oppositeListViewLoadingView.setVisibility(View.GONE);

    // Show the ListView Loading View and set it to refresh.
    listViewLoadingView.setVisibility(View.VISIBLE);
    listViewLoadingView.refreshing();

    if (doScroll) {
      // We need to disable the automatic visibility changes for now
      disableLoadingLayoutVisibilityChanges();

      // We scroll slightly so that the ListView's header/footer is at the
      // same Y position as our normal header/footer
      setHeaderScroll(scrollToY);

      // Make sure the ListView is scrolled to show the loading
      // header/footer
      mRefreshableView.setSelection(selection);

      // Smooth scroll as normal
      smoothScrollTo(0);
    }
  }

  @Override
  protected void onReset() {
    /**
     * If the extras are not enabled, just call up to super and return.
     */
    if (!mListViewExtrasEnabled) {
      super.onReset();
      return;
    }

    final LoadingLayout originalLoadingLayout, listViewLoadingLayout;
    final int scrollToHeight, selection;
    final boolean scrollLvToEdge;

    switch (getCurrentMode()) {
      case MANUAL_REFRESH_ONLY:
      case PULL_FROM_END:
        originalLoadingLayout = getFooterLayout();
        listViewLoadingLayout = mFooterLoadingView;
        selection = mRefreshableView.getCount() - 1;
        scrollToHeight = getFooterSize();
        scrollLvToEdge = Math.abs(mRefreshableView.getLastVisiblePosition() - selection) <= 1;
        break;
      case PULL_FROM_START:
      default:
        originalLoadingLayout = getHeaderLayout();
        listViewLoadingLayout = mHeaderLoadingView;
        scrollToHeight = -getHeaderSize();
        selection = 0;
        scrollLvToEdge = Math.abs(mRefreshableView.getFirstVisiblePosition() - selection) <= 1;
        break;
    }

    // If the ListView header loading layout is showing, then we need to
    // flip so that the original one is showing instead
    if (listViewLoadingLayout.getVisibility() == View.VISIBLE) {

      // Set our Original View to Visible
      originalLoadingLayout.showInvisibleViews();

      // Hide the ListView Header/Footer
      listViewLoadingLayout.setVisibility(View.GONE);

      /**
       * Scroll so the View is at the same Y as the ListView header/footer, but
       * only scroll if: we've pulled to refresh, it's positioned correctly
       */
      if (scrollLvToEdge && getState() != State.MANUAL_REFRESHING) {
        mRefreshableView.setSelection(selection);
        setHeaderScroll(scrollToHeight);
      }
    }

    // Finally, call up to super
    super.onReset();
  }

  @Override
  protected LoadingLayoutProxy createLoadingLayoutProxy(final boolean includeStart, final boolean includeEnd) {
    LoadingLayoutProxy proxy = super.createLoadingLayoutProxy(includeStart, includeEnd);

    if (mListViewExtrasEnabled) {
      final Mode mode = getMode();

      if (includeStart && mode.showHeaderLoadingLayout()) {
        proxy.addLayout(mHeaderLoadingView);
      }
      if (includeEnd && mode.showFooterLoadingLayout()) {
        proxy.addLayout(mFooterLoadingView);
      }
    }

    return proxy;
  }

  protected ListView createListView(Context context, AttributeSet attrs) {
    final ListView lv;
    if (VERSION.SDK_INT >= VERSION_CODES.GINGERBREAD) {
      lv = new InternalListViewSDK9(context, attrs);
    } else {
      lv = new InternalListView(context, attrs);
    }
    return lv;
  }

  @Override
  protected ListView createRefreshableView(Context context, AttributeSet attrs) {
    ListView lv = createListView(context, attrs);

    // Set it to this so it can be used in ListActivity/ListFragment
    lv.setId(android.R.id.list);
    return lv;
  }

  @Override
  protected void handleStyledAttributes(TypedArray a) {
    super.handleStyledAttributes(a);

    mListViewExtrasEnabled = a.getBoolean(R.styleable.PullToRefresh_ptrListViewExtrasEnabled, true);

    if (mListViewExtrasEnabled) {
      final FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,
          FrameLayout.LayoutParams.WRAP_CONTENT, Gravity.CENTER_HORIZONTAL);

      // Create Loading Views ready for use later
      FrameLayout frame = new FrameLayout(getContext());
      mHeaderLoadingView = createLoadingLayout(getContext(), Mode.PULL_FROM_START, a);
      mHeaderLoadingView.setVisibility(View.GONE);
      frame.addView(mHeaderLoadingView, lp);
      mRefreshableView.addHeaderView(frame, null, false);

      mLvFooterLoadingFrame = new FrameLayout(getContext());
      mFooterLoadingView = createLoadingLayout(getContext(), Mode.PULL_FROM_END, a);
      mFooterLoadingView.setVisibility(View.GONE);
      mLvFooterLoadingFrame.addView(mFooterLoadingView, lp);

      /**
       * If the value for Scrolling While Refreshing hasn't been explicitly set
       * via XML, enable Scrolling While Refreshing.
       */
      if (!a.hasValue(R.styleable.PullToRefresh_ptrScrollingWhileRefreshingEnabled)) {
        setScrollingWhileRefreshingEnabled(true);
      }
    }
  }

  @TargetApi(9)
  final class InternalListViewSDK9 extends InternalListView {

    public InternalListViewSDK9(Context context, AttributeSet attrs) {
      super(context, attrs);
    }

    @Override
    protected boolean overScrollBy(int deltaX, int deltaY, int scrollX, int scrollY, int scrollRangeX,
        int scrollRangeY, int maxOverScrollX, int maxOverScrollY, boolean isTouchEvent) {

      final boolean returnValue = super.overScrollBy(deltaX, deltaY, scrollX, scrollY, scrollRangeX, scrollRangeY,
          maxOverScrollX, maxOverScrollY, isTouchEvent);

      // Does all of the hard work...
      OverscrollHelper.overScrollBy(PullToRefreshListView.this, deltaX, scrollX, deltaY, scrollY, isTouchEvent);

      return returnValue;
    }
  }

  protected class InternalListView extends ListView implements EmptyViewMethodAccessor {

    private boolean mAddedLvFooter = false;

    public InternalListView(Context context, AttributeSet attrs) {
      super(context, attrs);
    }

    @Override
    protected void dispatchDraw(Canvas canvas) {
      /**
       * This is a bit hacky, but Samsung's ListView has got a bug in it when
       * using Header/Footer Views and the list is empty. This masks the issue
       * so that it doesn't cause an FC. See Issue #66.
       */
      try {
        super.dispatchDraw(canvas);
      } catch (IndexOutOfBoundsException e) {
        e.printStackTrace();
      }
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
      /**
       * This is a bit hacky, but Samsung's ListView has got a bug in it when
       * using Header/Footer Views and the list is empty. This masks the issue
       * so that it doesn't cause an FC. See Issue #66.
       */
      try {
        return super.dispatchTouchEvent(ev);
      } catch (IndexOutOfBoundsException e) {
        e.printStackTrace();
        return false;
      }
    }

    @Override
    public void setAdapter(ListAdapter adapter) {
      // Add the Footer View at the last possible moment
      if (null != mLvFooterLoadingFrame && !mAddedLvFooter) {
        addFooterView(mLvFooterLoadingFrame, null, false);
        mAddedLvFooter = true;
      }

      super.setAdapter(adapter);
    }

    @Override
    public void setEmptyView(View emptyView) {
      PullToRefreshListView.this.setEmptyView(emptyView);
    }

    @Override
    public void setEmptyViewInternal(View emptyView) {
      super.setEmptyView(emptyView);
    }

  }

}
